生成与authy桌面相同的otp代码

I try to generate totp code using this library same like authy.com desktop application. this is my current code :

package main

import (
    "time"

    "github.com/pquerna/otp/totp"

    "bufio"
    "fmt"
    "os"
)

func promptForPasscode() string {
    reader := bufio.NewReader(os.Stdin)
    fmt.Print("Enter Passcode: ")
    text, _ := reader.ReadString('
')
    return text
}

func main() {

    keySecret := "NK4KFDHUGRGMFKFEWRJ5EEOV6FT2IAKE"

    coded, _ := totp.GenerateCode(keySecret, time.Now().UTC())
    fmt.Println("code :", coded)

    fmt.Println("Validating TOTP...")
    // Now Validate that the user's successfully added the passcode.
    passcode := promptForPasscode()
    valid := totp.Validate(passcode, keySecret)
    if valid {
        println("Valid passcode!")
        os.Exit(0)
    } else {
        println("Invalid passocde!")
        os.Exit(1)
    }
}

The code is working, my problem is, the code generated by golang application is not the same like authy desktop application, what is wrong ?